1. Field of the Invention
This invention relates to a printer.
2. Description of the Prior Art
Along with the recent advancement of the electronic art, mechanical parts of a printer have been replaced by a motor, a solenoid, etc., thereby enhancing the reliability of the instrument.
This electric printer has a great merit of enhanced reliability while, on the other hand, it is expensive because the motor and the electrical elements of the control system therefore are more expensive than the mechanical parts.
Further, in the electric printer, a motor for rotatively driving a character wheel is mounted on a carriage which is provided with a character wheel, a ribbon feeding motor, a ribbon shift solenoid, a printing hammer, etc. This leads to a greater mass of the carriage and also to a larger size of the spacing motor for reciprocally moving the carriage parallel to the axis of the platen.
Therefore, to improve the printing speed, an effort to reduce the inertia of the character wheel has heretofore been made, but this has a limitation and the character wheel driving motor must be larger in size. This has necessarily led to a problem that a large spacing motor must be used.
Also, in the conventional printer, the character wheel driving motor is mounted on the carriage and so, the mass of the carriage is great. Therefore, to improve the printing speed, the inertia of the the character wheel must be reduced and the mass of the entire carriage must be minimized by the use of a small character wheel motor having a small mass to thereby enhance the response speed of the carriage driving motor. Since, however, reducing the inertia of the character wheel encounters a limitation, a considerably large character wheel driving motor must be used to improve the printing speed and this has necessarily led to an inconvenience that the carriage driving motor must also be larger.